Ephron is best known for her screenwriting work (Sleepless in Seattle; You've Got Mail), but her talent for witty dialogue flourishes in her second novel (after Hanging Up), set in Sakonnet Bay, Long Island, where freelance reporter and single mom Lily Davis moves from Manhattan with her 15-year-old son, Sam. Lily decided to move to the small town when she realized Sam was sneaking out to nightclubs and hiding a knife in his bureau drawer, but her efforts to give him safe harbor are thwarted by his sullen rebelliousness and his Klingon-speaking girlfriend, Deidre. An inveterate New Yorker, Lily is uncomfortable in the cozy, gossipy town and fearful of almost everything. Do the deer grazing on her front lawn have rabies? Are Sam's antisocial tendencies and dreadful haircut ""normal range behavior""? Has she become the town joke for insulting police Sgt. Tom McKee during an incident involving a dog whose head got stuck in a pitcher? Soon Lily has serious issues to worry about, such as the naked woman--dead, drugged or sleeping--she and Tom discover in a supposedly empty house. When the woman's body is later found after having been haphazardly buried by someone in a swampy area, Lily starts sleuthing to find out what happened. Not only does this investigation reveal a less than idyllic side to Sakonnet Bay, it also forces her to confront disturbing truths about her son, her divorce and her growing feelings for the married Tom. Despite billing herself as an ""irritating,"" liberated city woman, Lily tends to musings about family and divorce that reveal Ephron's moral to the story: divorce can be confusing and painful for kids, but a loving parent can still keep her child on track. Lily learns she can't safeguard her son merely by shielding him from big-city dangers. The road to this hard-earned lesson takes the reader through a novel that sparkles with lively characters. (May)